Among olefin compounds where a part or all of hydrogen atoms are substituted with a chlorine atom and a fluorine atom, that is, olefins containing chlorine and fluorine, some industrially-useful compounds are known, however, no method for simply and efficiently producing these compounds has been established yet. For example, Patent Document 1 discloses a method in which an olefin is reacted with fluorine gas in the presence of anhydrous hydrogen fluoride, however, this reaction is extremely exothermic and, hence, must be performed at an extremely low temperature, e.g., −70° C. In addition, by-products are produced in a large amount.
Consequently, if other olefins containing chlorine and fluorine could be simply and efficiently produced from industrially-easily-available fluorine-containing olefins such as R-1112, i.e., 1,2-dichloro-1,2-difluoroethylene, and R-1131a, i.e., 1-chloro-1-fluoroethylene under mild conditions, the method could be an extremely useful synthesis method as compared with already-existing methods.
On the other hand, olefin metathesis reaction that is a double bond recombination reaction with a metal catalyst (hereinafter this may be simply referred to as “olefin metathesis”) is widely utilized as a production method for olefins having various types of substituents. However, electron-deficient olefins having an electron-withdrawing substituent have low reactivity, and therefore use thereof in olefin metathesis is not easy. For example, Non-Patent Document 1 investigates the reactivity of olefins having various substituents and describes that the reactivity of electron-deficient olefins is low. In fact, olefins having a halogen such as a fluorine atom or a chlorine atom are electron-deficient olefins, and therefore there are few reports using them in olefin metathesis. For example, in Non-Patent Document 2, olefin metathesis of a ruthenium complex and vinylidene fluoride (i.e., 1,1-difluoroethylene) is investigated, but the report describes that the expected products, that is, ethylene and tetrafluoroethylene could not be obtained at all.